Reduced-order modeling for unsteady transonic flows around an airfoil

High-transonic unsteady flows around an airfoil at zero angle of incidence and moderate Reynolds numbers are characterized by an unsteadiness induced by the von Karman instability and buffet phenomenon interaction. These flows are investigated by means of low-dimensional modeling approaches. Reduced-order dynamical systems based on proper orthogonal decomposition are derived from a Galerkin projection of two-dimensional compressible Navier-Stokes equations. A specific formulation concerning density and pressure is considered. Reduced-order modeling accurately predicts unsteady transonic phenomena. (c) 2007 American Institute of Physics.